The second meiosis occurs in cytochalasin D-treated eggs of Corbicula leana even though it is not observed in control androgenetic eggs because the maternal chromosomes and centrosomes are extruded at first meiosis.

The hermaphroditic freshwater clam Corbicula leana reproduces by androgenesis. In the control (androgenetic development), all maternal chromosomes and maternal centrosomes at the meiotic poles were extruded as the two first polar bodies, and subsequently, second meiosis did not occur. But, in C. leana eggs treated with cytochalasin D (CD) to inhibit polar body extrusion, the second meiosis occurred. At metaphase-I, the spindle showed the typical bipolar structure and two spheroid centrosomes were located at its poles. All the maternal chromosomes were divided at anaphase-I, but they were not extruded as polar bodies due to the effects of CD. After completion of first meiosis, the maternal centrosomes split into four. At the second meiosis, twin or tetrapolar spindles were formed and two groups of maternal chromosomes divided into four sets of chromosomes. After the second meiosis, the spindle disassociated and the four maternal centrosomes disappeared. Four groups of maternal chromosomes transformed into the four female pronuclei. Male and female pronuclei became metaphase chromosomes of the first mitosis. The present study clearly indicates that typical meiosis systems still proceed in androgenetic triploid C. leana. We conclude that the androgenetic form may have arisen from the meiotic form.

Calmodulin binds to inv protein: implication for the regulation of inv function.

Establishment of the left-right asymmetry of internal organs is essential for the normal development of vertebrates. The inv mutant in mice shows a constant reversal of left-right asymmetry and although the inv gene has been cloned, its biochemical and cell biological functions have not been defined. Here, we show that calmodulin binds to mouse inv protein at two sites (IQ1 and IQ2). The binding of calmodulin to the IQ2 site occurs in the absence of Ca(2+) and is not observed in the presence of Ca(2+). Injection of mouse inv mRNA into the right blastomere of Xenopus embryos at the two-cell stage randomized the left-right asymmetry of the embryo and altered the patterns of Xnr-1 and Pitx2 expression. Importantly, inv mRNA that lacked the region encoding the IQ2 site was unable to randomize left-right asymmetry in Xenopus embryos, implying that the IQ2 site is essential for inv to randomize left-right asymmetry in Xenopus. These results suggest that calmodulin binding may regulate inv function. Based on our findings, we propose a model for the regulation of inv function by calcium-calmodulin and discuss its implications.

Prognostic factors in early gastric cancer.

BACKGROUND/AIMS: Opportunities of observing patients with recurrent early gastric cancer are rare. Assessment of prognostic factors for the recurrence of early gastric cancer is important for determining adequate strategies for managing early gastric cancer. METHODOLOGY: Clinicopathologic variables were compared in 8 patients with and 453 without recurrence who were followed for over 5 years after curative resection. Expression of mutant p53 and Ki-67 was evaluated in 16 patients with n2 or above. RESULTS: Eight patients died of gastric cancer with recurrence. There were no inter-group differences in mean diameter, histologic classification, patterns of infiltrating growth, or cancer-stroma relationship; but macroscopic appearance, depth of invasion, lymphatic invasion, venous invasion and lymph node metastases were significantly more frequent on univariate analysis in those with recurrence. Lymph node metastases was an independent prognostic factor by the Cox proportional hazards regression model. In patients with n2 or above, mutant p53 expression was higher in recurrent than in nonrecurrent cases. CONCLUSIONS: Lymph node metastasis was the only independent prognostic factor for the recurrence of early gastric cancer. The expression of mutant p53 may be an indicator of recurrence in patients with n2 or above.

Vascular endothelial markers, von Willebrand factor and thrombomodulin index, are specifically elevated in type 2 diabetic patients with nephropathy: comparison of primary renal disease.

To elucidate the hypothesis that albuminuria in diabetic subjects reflects widespread vascular damage, plasma markers for vascular endothelial damage was measured in diabetic subjects with various degrees of albuminuria and compared to results in patients with primary renal disease. The groups consisted of 31 non-diabetic patient controls with normoalbuminuria, 109 type 2 diabetic patients with normo- micro- and macro-albuminuria, and 16 proteinuric patients with primary renal disease. Endothelial markers, plasma von Willebrand factor (vWF) and thrombomodulin (TM), were measured by enzyme-linked immunosolvent assay and enzyme immunoassay (EIA) methods, respectively. Plasma vWF levels were similar in controls (119+/-7%, mean+/-S.E.M.) and diabetic patients with normoalbuminuria (139+/-6), but significantly elevated in diabetic patients with microalbuminuria (174+/-11) and macroalbuminuria (204+/-17), while the level was not increased in patients with primary renal disease (124+/-11). Because plasma TM level was strongly affected by kidney function, TM index (TM (FU/ml)/serum creatinine (mg %)) was used as an endothelial marker. The TM index was substantially increased in diabetic patients with overt nephropathy compared with controls (5.29+/-2.98 vs. 2.35+/-0.85), whereas this was not observed in patients with primary renal disease (3.25+/-0.29). Both vWF and TM index were significantly higher in diabetic patients with retinopathy than in the patients without retinopathy. These results suggest that generalized vascular endothelial damage occurs in diabetic nephropathy including the microalbuminuric stage, which is not attributed to kidney damage per se.

Indications for paraaortic lymph node dissection in gastric cancer patients with paraaortic lymph node involvement.

BACKGROUND/AIMS: The surgical results for stage IVb gastric cancer remain very poor. The purpose of the current study is to reveal indications for paraaortic lymph node dissection in stage IVb gastric cancer patients with paraaortic lymph node involvement by analyzing prognostic factors for 3-year survival of stage IVb gastric cancer patients followed by curative B resection. METHODOLOGY: The 3-year survival in clinicopathologic variables were compared by univariate analysis. Using Cox proportional hazards regression model, independent prognostic factors were identified from 11 variables. RESULTS: Overall 5-year survival in stage IVb was 26.5%; mean survival was 19 months. Using univariate analysis, p53 expression significantly influenced 3-year survival. Using Cox proportional hazards regression model, the number of total positive lymph nodes, the number of positive paraaortic lymph nodes, and p53 expression were independent prognostic factors. CONCLUSIONS: In stage IVb, paraaortic lymph node dissection should be indicated in patients with < or = 10 total positive lymph nodes, and < or = 3 positive paraaortic lymph nodes or p53 expression < or = 50%. This indication can be applied according to the preoperative imaging, the staining of p53 by endoscopic biopsy specimens and the intraoperative microscopic evaluation of dissected lymph nodes.

Hepatocellular carcinoma arising in an elderly male with primary biliary cirrhosis.

We report the case of an elderly male with asymptomatic primary biliary cirrhosis (PBC) who developed a hepatocellular carcinoma (HCC). The 89-year-old man, who was otherwise healthy, was admitted for investigation of mild hepatic dysfunction, which had been detected during a routine physical check-up. Serum chemistry, positive anti-mitochondrial antibody (M2) and liver biopsy results led to a diagnosis of PBC. Three years later, at age 92, computed tomography (CT) and ultrasound scans of his abdomen revealed a large hepatic tumour, which was confirmed on liver biopsy to be HCC. The tumour ruptured 3 months after diagnosis and the patient was successfully stabilized by coil embolization of his right hepatic artery. We believe that, to date, this is the oldest reported patient to have had interventional radiology for the management of HCC.

All meiotic chromosomes and both centrosomes at spindle pole in the zygotes discarded as two polar bodies in clam Corbicula leana: unusual polar body formation observed by antitubulin immunofluorescence.

To understand the unusual polar body formation in the androgenetic clam, Corbicula leana, whole-mount eggs stained with monoclonal antibodies against alpha-tubulin, gamma-tubulin, and 4'-6'-diamidino-2-phenylindole were examined. The meiotic spindle was located at the peripheral region of the egg at metaphase I, and its axis was parallel to the egg surface. After segregation of chromosomes at anaphase I, cytoplasmic bulges formed at both meiotic spindle pole sites. Centrosomes were located at the apical portion of the each bulge. From the apical portion of the bulge a bundle of astral microtubules radiated toward the bulge base in late anaphase resembling a half spindle. Maternal chromosomes and both centrosomes were all distributed in two "first polar bodies" and were eventually discarded. After the polar body formation only one male pronucleus existed in the egg cytoplasm. The present study showed that the anaphase microtubules originating from a single aster can induce the polar body formation without overlapping of microtubules from the opposing aster.

[Significance and effects of intraperitoneal cisplatin administration for ovarian cancer].

We studied the efficacy and safety of combination chemotherapy in which a high-dose platinum agent was administered intraperitoneally (i.p.) plus intravenously (i.v.) to 22 patients with stage III ovarian cancer. The chemotherapy consisted of etoposide (i.p.), cisplatin (i.p.), and carboplatin (i.v.). Each course was repeated every 4 weeks and a maximum of 5 courses was given in the 6 months following the initial surgery. As a control, 13 patients received different chemotherapy (CAP etc.) in which cisplatin, cyclophosphamide and doxorubicin pirarubicin hydrochloride were administered. The mean (SD) total dose of cisplatin in the patient group group (790.6 +/- 317.0 mg/m2) over the 6 months was significantly higher than in the control group (377.2 +/- 215.1 mg/m2). The overall response rate (CR + PR) 6 months after the completion (95.5%) was significantly higher in the study patients than in the control group (53.1%). The 1, 3, 5-year survival rates were significantly higher in the EPJ group (91.0, 59.0, 42.1%) than in the control group (53.8, 15.4, 15.4%). There was no significant difference in renal toxicity or bone marrow suppression (leukopenia and thrombocytopenia) between the two groups. EPJ therapy allowed an increased dose of cisplatin in the treatment of ovarian cancer without enhancing renal toxicity, resulting in higher response and survival rates. This study demonstrated that this therapy is an effective and well-tolerated regimen.

Structural features and hypoglycemic activity of a polysaccharide (CS-F10) from the cultured mycelium of Cordyceps sinensis.

A polysaccharide (CS-F10) purified from a hot water extract of the cultured mycelium of Cordyceps sinensis was composed of galactose, glucose and mannose in a molar ratio of 43:33:24; its molecular weight was estimated to be about 15000. The results of chemical and spectroscopic investigations suggest that CS-F10 has a comb-type structure, and has alpha-D-glucopyranosyl residues on the terminal of the side-chains and characteristic sugar residues of C. sinensis i.e., 1,5-linked beta-D-galactofuranosyl residues. CS-F10 significantly lowered the plasma glucose level in normal, streptozotocin (STZ)-induced diabetic and epinephrine-induced hyperglycemic mice after intraperitoneal administration (50 mg/kg). Administration of CS-F10 to STZ-induced diabetic mice significantly increased the activity of hepatic glucokinase. A significant reduction in the hepatic glucose output was observed following the infusion of CS-F10 using the perfused rat liver. CS-F10 also significantly decreased protein content of facilitative glucose transporter isoform 2 (GLUT2) from rat liver following i.p. administration. These effects presumably contribute to the hypoglycemic activity.

A new instrument for hemostatic vascular management in endoscopic surgery: diode laser (STATLase-SDL) and its handpiece (dual hook).

OBJECTIVE: The authors described experimental data in hemostatic vascular transection using a STATLase-SDL with a 780-865 nm GaA/As diode wavelength and its handpiece, Dual Hook (DH). SUMMARY BACKGROUND DATA: The STATLase-SDL and DH are newly developed devices for endoscopic surgery. It seems that the device has improved hemostatic cutting ability. METHODS: The DH was applied to the abdominal aorta (< 2 mm) of Japanese white rabbits (n = 15) under general anesthesia. Tissue temperature during laser transection and interluminal bursting pressures were measured. Histopathological examinations at the cut end were carried out by hematoxylin-eosin (H&E) and elastica Van Gleson's (EVG) stainings. To investigate short-term effects 11 days postoperatively, the cut ends of the vessels were examined histologically in the heminephrectomy group. RESULTS: The DH hemostatistically cut through arteries up to 2 mm in diameter. Temperatures at the inner hook and in adjunct tissue were higher than 160 degrees C, while that at the outer hook was lower than 80 degrees C. The bursting pressures immediately after transection was 307.2 +/- 35.2 mm Hg at a laser power of 8 W (n = 5), and 295.6 +/- 28.7 mm Hg at 10 W (n = 5). Histological examination of the transected sites on the vessels revealed well-opposed tissue welding of the vascular wall. Absence of fragmentation in the welding of the internal elastic lamina is crucial for closure of the vessel stump. Up to 11 days postoperatively, there were no direct complications related to the use of the DH. CONCLUSIONS: The STATLase-SDL and DH have good hemostatic cutting ability and might be suitable for endoscopic surgery.

Changes in DNA copy number in primary gastric carcinomas by comparative genomic hybridization.

We examined 33 primary gastric carcinomas using comparative genomic hybridization to detect changes in the DNA copy number and the chromosomal location of these changes. Ninety-four percent (31 of 33) showed 1 or more DNA copy number changes, such as increases at 2p23-p25 (observed in 21% of the total cases), 3q26.3-q27 (24%), 7p15 (24%), 9p22-pter (18%), and 13q22-q34 (21%) and decreases at 1p34.2-p36.2 (18%) and Y (52%). Histological examination indicated that increases at 3q26.1-q26.3 and 7p15 and decreases at 1p36.1-p36. 2 and Y were commonly observed in both differentiated and undifferentiated types. Increases at 3q27, 6q23-q25, and 7cen-p14 and decreases at 1p34.2-p35 and 17p12 were predominantly observed in the differentiated type, and increases at 2p23-pter, 9p22-pter, and 13q31-qter and a decrease at 6p21.3 were predominantly observed in the undifferentiated type. In addition, clinical staging of tumors showed that increases at 2p23-p25, 7p14-p21, 7q31-q32, and 9p22-pter and a decrease at Y were observed in early-stage tumors, whereas increases at 9q32-q33 and 15q26 were observed only in late-stage tumors. Many of the abnormalities detected in this study were not previously reported in gastric carcinomas. Our comparative genomic hybridization results indicate the presence of genetic alterations that may play some important role in the development and progression of gastric carcinomas.

Healing process of vascular cutting edge using an Nd:YAG laser bipolar dissector.

The wound healing process was histopathologically investigated in a rabbit femoral artery (n = 48) after transection using a laser bipolar dissector (LBD, 1064nm the Nd:YAG bipolar contact laser) with laser power of 13W in 0.5-sec pulses. The cutting edges were harvested immediately (n = 6) and at 1 (n = 6), 4 (n = 6), and 7 (n = 6) days, 2 (n = 6), 3 (n = 6), and 4 (n = 6) weeks, and 6 months (n = 6), and evaluated by light microscopy. During the postoperative period, no perforation was seen in the 48 transected sites with the LBD. The healing process after LBD transection was accomplished within 2 weeks by organization of the intraluminal thrombus and by the formation of granulation tissue outside the adventitia of vessels. Characteristic morphological changes after LBD transection were recognized in the tapering area, i.e., cartilage and bone formation. Cartilaginous foci (n = 6) were observed in the media at 4 weeks after transection, and osseous foci (n = 3) in subendothelial space at 6 months. These observations may suggest that the heterotopic cartilaginous and osseous metaplasia of a vessel wall may be a result of the biostimulative effects of the Nd:YAG laser.

[A case of advance colon cancer responding to sequential methotrexate and 5-fluorouracil therapy].

A 60-year-old female was diagnosed by X-ray examination and endoscopy as ascending colon cancer. Ultrasonography and computed tomography revealed two metastatic tumors in the liver. Abdominal surgery revealed peritoneal disseminations, massive lymph node metastasis and direct invasion of the transverse colon and ileum. From pathological examination the diagnosis was moderately differentiated adenocarcinoma. After right hemi-colectomy, sequential methotrexate and 5-fluorouracil therapy as well as oral administration of UFT, liver metastasis disappeared and no sign of ascites was found in this case. Complete response time was over 8 months. There have been no severe complications.

[Angioarchitecture of the lower esophagus in portal hypertension].

In order to clarify the angioarchitecture of the palisade zone in the lower esophagus for portal hypertensive cases, we examined the thirty untreated autopsy cases of portal hypertension. At autopsy, barium added gelatin was injected from gastric coronary vein of the gastric wall and we observed them histologically and histometrically. 1) In portal hypertension, the palisade zone has increasing veins running in the submucosa, which veins belonged originally to the lamina propria. 2) A difference in angioarchitecture is present between the palisade and truncal zones. 3) The palisade zone in esophageal varices was classified into two types of angioarchitecture by Hashizume. Our 30 cases were composed of 22 cases with palisading type and of 8 those with bar type. The later showed well developed varices.

[A case of localized pleural mesothelioma].

A 68-year-old male with localized pleural mesothelioma was described. The tumor was removed surgically in association with left upper pulmonary lobe and regional lymph nodes, since low grade malignancy had been suggested by preoperative needle biopsy. The operative and macroscopic findings revealed that the tumor was well encapsulated and arise from visceral pleura of S3 segment of left upper lobe, projecting into pleural cavity as a pedunculated mass. The tumor measured 9 X 6 X 4 cm in diameter. Based on electron microscopic and immunohistochemical findings of the tumor, the origin of tumor cells was discussed.